Heavy machinery is found in many factories, rail yards, repair shops and other locations where large items need to be moved and positioned. For example, lifting machinery is necessary to repair rail cars, engines and other railway vehicles and machinery. The lifting machinery is often made up of large support structures using hydraulic pistons, screws or large motors to move machinery. Because of the size of the lifting machinery and the size of machinery to be moved, it is often advantageous to place the lifting machinery below ground level, typically in a foundation.
In the case of a rail car lifting or positioning machinery such as a repair stand or a turntable, it is desirable that the gap between the rails on the ground and the rails on the positioning machine be minimized. In the case of a turntable, the foundation must be sufficiently round so that the turntable can freely rotate without rubbing against the foundation. A difficulty associated with minimizing gaps and rubbing is that the machinery sits in a foundation that is manufactured using concrete forms. The concrete forms may be built from wooden boards and cut and designed on site. The machinery is often built from large steel plates and/or beams that are cut and fit at the point of manufacture. Because the foundation and the machinery are built separately, the foundation often needs modifications when the machinery is installed on site to adjust the tolerances and gaps for ideal operation of the machinery within the foundation.
Current practice uses a number of foundation embedments to create complicated sections of a foundation. In order to properly locate each embedment, a number of variables may need to be properly surveyed or measured to allow for correct installation. Variables include, for example, center, center line, perimeter and depth of the foundation. Locating center alone is often a surveying task that can take a substantial amount of time to complete. Once center is located, a number of holes must be drilled in a flat foundation so that anchor bolts can be installed. The anchor bolts affix the machinery to the foundation, and the pattern of the anchor bolts must be within tight tolerances so that the machinery can easily bolt to the foundation. Again, locating the center and setting the pattern of the bolts can be a lengthy and costly surveying task.
Often, a general contractor responsible for pouring concrete has difficulties achieving the tolerances required for a turntable to operate correctly within a foundation. Since the tolerance requirements are so high relative to what is often required of general contractors, locating center and bolt holes within a foundation is a time consuming and expensive process. Additional problems with tolerances of concrete pouring may require alterations to foundations after pouring, which are a time consuming and labor intensive.
Additionally, current practice for installation of a turntable may require that the turntable is installed in a partially completed foundation, and then the foundation is completed once the turntable is in place. Often, the first part of the foundation is poured, and then the general contractor leaves the job site because of the length of time required to install the turntable. Then the turntable is installed, and once installed, the general contractor is brought back to the job site to complete the foundation. This requires additional costs associated with re-mobilizing the general contractor's foundation pouring operations.
U.S. Pat. No. 7,798,067 to Starnes discloses a thin turntable having bearings disposed between a ground-engaging member and a load-supporting platform. A motor support box is located below the ground engaging member, the motor support box housing the motor assembly. An intermediate load transfer unit having bearing elements is located between the ground-engaging member and the load-supporting platform. The ground engaging unit of Starnes does not contain the entire turntable. The ground-engaging member has load surfaces that interact with the bearings of the intermediate load transfer unit.
U.S. Patent Application Publication No. 2007/0175353 A1 to Jeffs discloses a vehicle turntable with a housing having rollers within the housing. The housing rollers contact and support the turntable member. The vehicle turntable is pre-assembled with the housing, and the housing is an integral part of the turntable's ability to turn. A module adapted to receive completed machinery is not disclosed.
U.S. Pat. No. 7,966,939 to Holt discloses a foundation having a circular trench with an inner ring and an outer ring mounted within the circular trench. The two rings have rollers affixed thereon, and a bar assembly rests on the rollers. The turntable is assembled onto the foundation after the foundation is poured. A module adapted to receive completed machinery is not disclosed.
There is a need for improved lifting and positioning machinery that overcomes the disadvantages of the prior art. Much of the prior art is directed towards avoiding the use of a foundation for machinery such as a turntable. Although avoiding the use of a foundation for some applications may be acceptable, a foundation is often necessary for heavy loads, because the machinery must be stiff enough to support the heavy load. This avoidance of foundations in the prior art shows a need for machinery, such as a turntable, having an improved installation method.
It is therefore desirable to provide a method of installation for the improved machinery that reduces or eliminates the need for modifications to a foundation after the foundation material is cured or set.
It is further desirable to provide an improved method of installation for machinery that is more cost effective and takes less time.
It is further desirable to provide a method of installation for a turntable that allows a foundation to be built with tighter tolerances than prior art methods.